Pallet for sintering machines

ABSTRACT

A sintering machine pallet assembly includes a main pallet frame and one or more intermediate sectional frames interposed between the main pallet frame and conventional grate bars.

United States Patent Inventors Appl. No. Filed Patented Assignee PALLET FOR SINTERING MACHINES Primary Examiner-Gerald A. Dost Anorneys- Sherman H. Barber and Olin E. Williams 5 Claims, 4 Drawing Figs.

75/5 ABSTRACT: A sintering machine pallet assembly includes a lnt.Cl B60g 11/22 main pallet frame and one or more intermediate sectional Field of Search 266/20, 21; frames interposed between the main pallet frame and conven- 75/5 tional grate bars.

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INVENTORS KURT REINFELD z; OIL/P N. ASS/IR PALLET FOR SINTERING MACHINES BACKGROUND OF THE INVENTION The present invention relates to sintering and, more particularly, to an improved pallet for use in sintering machines.

Experience shows that, after a sintering machine has been in service for a period of time, the individual pallets, on which the material to be indurated is supported, undergo progressive sagging crosswise of the machine. The sagging is caused by a combination of mechanical cycling and thermal loads. The mechanical cycling and thermal loads produce compressive yielding in the uppermost fibers of the pallet cross-ribs, which effects a shortening of the top of the cross-rib wherefore the cross-ribs sag downward.

The top surfaces of the cross-ribs, being closest to the heat of sintering or induration, become much hotter than the lower portion of the ribs. Wherefore, due to the restraining influence of the cooler bottom portion, the upsetting action occurs in the upper portion.

Eventually, the sagging progresses to the point where the machine can no longer be operated, and at this time it is necessary either to straighten the pallets or to replace them.

H eretofore, a number of suggestions have been made which are known from the prior art to shield the top portion of the pallet ribs from the heat of sintering of induration. Attempts have been made to produce removable upper pallet portions, but such efforts have not proved to be entirely satisfactory, mainly because the pallet frame was not sufficiently removed from the heat of sintering or induration, and the pallet frame continued to warp and sag.

The present invention is directed to a pallet having one or more sectional intennediate frames which are interposed between conventional grate bars and a main pallet subframe.

SUMMARY OF THE INVENTION A sintering machine pallet comprises a subframe, a plurality of intermediary sectional frames that coact with each other and with the subframe to hold the intermediary sectional frames in place; a plurality of grate bars arranged on the intermediary frames; and means for securing the intermediary sectional frames, to the subframe.

For a further understanding of the invention and for features and advantages thereof, reference may be made to the following description in conjunction with the drawing which shows for the purpose of exemplification one embodiment of the invention. a

BRIEF DESCRIPTION OF THE DRAWING In the drawings:

FIG. 1 is a schematic plan view of a pallet for a sintering machine incorporating the present invention;

FIG. 2 is a sectional view along line Il--ll of FIG. 1;

FIG. 3 is a sectional view along line Ill-llI of FIG. 2; and

FIG. 4 is a perspective, exploded view of the pallet portion shown in FIG. 1 with portions of the structure omitted for clarity.

DETAILED DESCRIPTION A pallet frame 11, as shown in FIG. 1, includes a main subframe 13, an intermediate frame 15, grate bars 17, and pallet side frames 19.

The main pallet subframe 13 includes a plurality of elongate spaced-apart ribs 21 that are interconnected at their ends by side members 23, and that are interconnected along their length by a plurality of spaced-apart intercostal webs 25.

Between adjacent ribs 21 there are flat, horizontally extending, intercostal locking plates 27 which have a rectangular shaped notch 29 in one edge.

The side members 23 carry a pair of spaced apart shaft support bosses 31 that are bored, as at 33, to receive the shaft of a conventional pallet-supporting wheel (not shown). Each shaft-supporting boss 31 has a tongue 35 on its top surface that coacts with a matching groove 37 in a retainer 39 that locks and maintains the intermediate frames 15 in place.

The intermediate frame 15 is comprised of a plurality of sections 15a, 15b, and each section includes spaced-apart parallel tee-shaped bars 41, and spaced-apart parallel angleshaped bars 43. The angle-shaped bars 43 form the sides of the intermediate frame 15, and both the tee-shaped bars 41 and angle-shaped side bars 43 are connected together at their respective ends by a elongate rectangular bar 45. The angleshaped side bars 43, however, are notched at 47, as shown in FIG. 2, so that adjacent sections 15a, 15b of the intermediate frame 15 may, by mutual cooperation, act as if the intermediate sections were a single unitary intennediary frame. That is to say, a portion of the pallet section 15b overlaps an underlying portion of the pallet section 15a.

Depending from each rectangular bar 45 are a plurality of tee-shaped lugs 49 that are so arranged that the crossbar portion 51 of the tee-shaped lug is parallel to the rectangular bar 45.

From FIG. 3 it will be noted that the conventional grate bars 17 are disposed between adjacent tee-bar members 41 and between adjacent tee-bar and angle-bar members 43, 41 respectively. The great bars 17 are provided with depending hook-shaped lugs 53 that cooperate with the flange portions of adjacent tee-bar and angle-bar members 43, 41 respectively.

However, each pallet 11 is provided with four end grate bars 54 which are disposed in pairs at each end of the pallet 11. These grate bars 54 coact with locking bar members described thereinafter to keep and maintain all of the grate bars 17 in position.

The pallet side frame 19 is secured in position by means of grate bar locking members or retainers 55 that are disposed at the four corners of the pallet 11, and that are also disposed at about the midlength point of the side members 46. The grate bar retainer 55 has a wedge-shaped head portion 59 that is integrally formed with an elongate rectangular tail portion or handle 61 that extends through matching rectangular holes 63 in both the upstanding vertical flange portion 50 and the pallet side frame 19. Any suitable means, such as a cotter pin 65, or the like, passing through the tail portion as shown, may be employed to keep the grate bar retainers 55 in position.

The pallet 11 is assembled in the following manner. An intermediate frame section such as 15b, for example, is placed on the main subframe so that one end is just short of the longitudinal centerline of the pallet. The intermediate frame section 15b, is then moved laterally so that the one end is at the longitudinal centerline. As the pallet section is moved laterally, the lugs on the intermediate frame section cooperate with the notches in the locking plates, and the intermediate frame section is then secured in place.

A second intermediate frame such as 15a for example is then placed on the main pallet subframe and is moved laterally so as to abut the first intermediate frame. The two intermediate frames sections l5a, 15b are so positioned that one end portion of frame section 15b overlaps a portion of the frame section 15a. Also, the second intermediate frame is secured in place by lugs coacting with notched locking plates forming a portion of the subframe. The intermediate frame sections are adapted to cooperate so that the overlapping frame section prevents the underlying frame section from becoming dislodged.

Other intermediate pallet frames on both sides of the pallet are similarly installed until all frame sections are in place. The intermediate pallet frames 15 are finally locked in position by inserting the retainers 39 on the bosses 31 located on both side members of the main subframe 13. Thus, it should be clear that the intermediate frames are now interlocked with the main pallet subframe and with each other so that the intermediate frames cannot become dislodged and fall off when the pallet is upside down in the return pallet train. Then, the pallet grate bars are installed. When all grate bars are in place, the pallet side frame is installed and is locked in place by means of the grate bar mechanism.

Those skilled in the art will recognize from the foregoing description of one embodiment of the invention several significant features and advantages among which are:

That the sectional intermediate frames separate the pallet ribs from the grate bars, wherefore the temperature of the pallet ribs is considerably less than the temperature of the grate bars and warping of the pallet subframe is significantly reduced;

That the intermediate frames are sectionalized to reduce the amount of thermal warpage of each such frame; and

That the intermediate frames are loosely secured to the main pallet subframe wherefore thermal stresses are not transmitted from the intermediate frames to the subframe and vice versa.

We claim:

l. in a sintering machine having a series of interconnected pallets that form a travelling grate, an improved pallet assembly comprising:

a. a subframe having a plurality of notched plates;

b. a plurality of intermediary sectional frames disposed on said subframe that coact with each other and with said subframe, at least some of said sectional frames being provided with depending lugs adapted to coact with said notched plates, said sectional frames having notched ends that cooperate in overlapping and underlying relation with adjacent sectional frames, and with at least other sectional frames disposed adjacent the side edges of said subframe having depending lugs that coact with said notched plates and with one notched overlapping end that coacts with an underlying end of an adjacent sectional frame;

a plurality of grate bars arranged on said intermediary sectional frames;

d. a plurality of end grate bars disposed at the sides of said intermediary frames;

e. a pallet side frame that coacts with said intermediary frame;

f. a plurality of locking mechanisms mounted to said pallet side frame, each mechanism having a head portion that cooperates with an adjacent end grate bar to maintain said end grate bar and said other grate bars in position on said pallet frame;

g. a plurality of bosses on said subframe for mounting thereto shafts carrying wheels; and

h. locking means cooperating with said wheel bosses and said intermediary frame sections to secure said intermediary frames to said subframe.

2. in a sintering machine having a series of interconnected pallets that form a traveling grate, an improved pallet assembly comprising:

a. a subframe having a plurality of notched plates;

b. a plurality of intermediary frames coacting with said subframes and having lugs that coact with said notched plates and hold said intermediary frames in place;

c. a plurality of grate bars arranged on said intermediary frames; and

d. means for mounting rollers on said pallet.

3. The structure of claim 2 wherein:

a. each intermediary frame has an end shaped to coact with an end of an adjacent intermediary frame;

4. The structure of claim 3 wherein:

a. the shaped end of said intermediary frame is notched and overlaps a notched portion of an adjacent intermediary frame.

5. In a sintering machine having a series of interconnected pallets that form a traveling grate, an improved pallet assembly comprising:

a. a subframe;

b. a plurality of intermediary frames that coact with each other and with the subframe;

c. a plurality of grate bars arranged on said intermediary frame;

d. means for holding said intermediary frames on said subframe; e. a plurality of end grate bars disposed at the sides of said intermediary frames;

f. a pallet side frame that cooperates with said intermediary frames;

g. means for securing said pallet side frame to said intermediary frame adjacent the edge ofsaid subframe;

h. means securing the intermediary pallet to said subframe;

and

i. means for mounting rollers to said pallet. 

1. In a sintering machine having a series of interconnected pallets that form a travelling grate, an improved pallet assembly comprising: a. a subframe having a plurality of notched plates; b. a plurality of intermediary sectional frames disposed on said subframe that coact with each other and with said subframe, at least some of said sectional frames being provided with depending lugs adapted to coact with said notched plates, said sectional frames having notched ends that cooperate in overlapping and underlying relation with adjacent sectional frames, and with at least other sectional frames disposed adjacent the side edges of said subframe having depending lugs that coact with said notched plates and with one notched overlapping end that coacts with an underlying end of an adjacent sectional frame; c. a plurality of grate bars arranged on said intermediary sectional frames; d. a plurality of end grate bars disposed at the sides of said intermediary frames; e. a pallet side frame that coacts with said intermediary frame; f. a plurality of locking mechanisms mounted to said pallet side frame, each mechanism having a head portion that cooperates with an adjacent end grate bar to maintain said end grate bar and said other grate bars in position on said pallet frame; g. a plurality of bosses on said subframe for mounting thereto shafts carrying wheels; and h. locking means cooperating with said wheel bosses and said intermediary frame sections to secure said intermediary frames to said subframe.
 2. In a sintering machine having a series of interconnected pallets that form a traveling grate, an improved pallet assembly comprising: a. a subframe having a plurality of notched plates; b. a plurality of intermediary frames coacting with said subframes and having lugs that coact with said notched plates and hold said intermediary frames in place; c. a plurality of grate bars arranged on said intermediary frames; and d. means for mounting rollers on said pallet.
 3. The structure of claim 2 wherein: a. each intermediary frame has an end shaped to coact with an end of an adjacent intermediary frame;
 4. The structure of claim 3 wherein: a. the shaped end of said intermediary frame is notched and overlaps a notched portion of an adjacent intermediary frame.
 5. In a sintering machine having a series of interconnected pallets that form a traveling grate, an improved pallet assembly comprising: a. a subframe; b. a plurality of intermediary frames that coact with each other and with the subframe; c. a pluraliTy of grate bars arranged on said intermediary frame; d. means for holding said intermediary frames on said subframe; e. a plurality of end grate bars disposed at the sides of said intermediary frames; f. a pallet side frame that cooperates with said intermediary frames; g. means for securing said pallet side frame to said intermediary frame adjacent the edge of said subframe; h. means securing the intermediary pallet to said subframe; and i. means for mounting rollers to said pallet. 